A conventional light-emitting diode (LED) is used as a light source or illumination device. The LED is widely applied to various sites or environments. In conventional technique, a light-emitting module is often used to project white light onto an exhibited environment or product. The light-emitting module includes blue light LED. The light emitted from the blue light LED energizes yellow fluorescent powder or phosphor to produce white light emitting module. Also, red, blue and green LED can be combined into a white light emitting module.
In conventional technique, a wavelength conversion material (such as fluorescent powder or phosphor with a wavelength ranging from 500 nm to 780 nm) is disposed on blue light LED with a wavelength ranging from 440 nm to 460 nm. The wavelength conversion material serves to convert the light emitted from the blue light LED into colored light of green to red. The colored light is mixed with the light emitted from a deep blue light LED with a light wavelength ranging from 400 nm to 440 nm to achieve a white light output effect.
In the above technique, the wavelength conversion material converts the light emitted from the blue light LED into colored light of green to red. The colored light is mixed with the deep blue light emitted from the deep blue light LED with a certain wavelength or short wavelength to achieve a white output light. The light emitted from the deep blue light LED is not converted by the wavelength conversion material to change the wavelength. Moreover, the light emitted from the deep blue light LED is not a normal blue light so that the light-emitting module as a whole can output the white light.
With respect to the structure and application of the conventional white light emitting module, the conventional technique cannot adjust the white light rendering effect according to the product attribute, environment or application condition. The conventional technique cannot solve the problem of non-uniform mixing of the light.
It is therefore tried by the applicant to provide a light-emitting module in which the combination of the LED and the wavelength conversion material is redesigned in use form and structure to distinguish the light-emitting module from the conventional technique and improve the application thereof and enhance the white light rendering effect. Also, the light-emitting module of the present invention minimizes the possibility that the light is non-uniformly mixed as happening in the conventional technique.